{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,24]],"date-time":"2026-01-24T19:17:52Z","timestamp":1769282272525,"version":"3.49.0"},"reference-count":47,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2022,8,9]],"date-time":"2022-08-09T00:00:00Z","timestamp":1660003200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003246","name":"Dutch Technology Foundation TTW","doi-asserted-by":"publisher","award":["14126"],"award-info":[{"award-number":["14126"]}],"id":[{"id":"10.13039\/501100003246","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003246","name":"Dutch Technology Foundation TTW","doi-asserted-by":"publisher","award":["NNX16AQ24G"],"award-info":[{"award-number":["NNX16AQ24G"]}],"id":[{"id":"10.13039\/501100003246","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ministry of Economic Affairs","award":["14126"],"award-info":[{"award-number":["14126"]}]},{"name":"Ministry of Economic Affairs","award":["NNX16AQ24G"],"award-info":[{"award-number":["NNX16AQ24G"]}]},{"name":"NASA-THP","award":["14126"],"award-info":[{"award-number":["14126"]}]},{"name":"NASA-THP","award":["NNX16AQ24G"],"award-info":[{"award-number":["NNX16AQ24G"]}]},{"name":"Center for Remote Sensing, University of Florida","award":["14126"],"award-info":[{"award-number":["14126"]}]},{"name":"Center for Remote Sensing, University of Florida","award":["NNX16AQ24G"],"award-info":[{"award-number":["NNX16AQ24G"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>For a good interpretation of radar backscatter sensitivity to vegetation water dynamics, we need to know which parts of the vegetation layer control that backscatter. However, backscatter sensitivity to different depths in the canopy is poorly understood. This is partly caused by a lack of observational data to describe the vertical moisture distribution. In this study, we aimed to understand the sensitivity of L-band backscatter to water at different heights in a corn canopy. We studied changes in the contribution of different vertical layers to total backscatter throughout the season and during the day. Using detailed field measurements, we first determined the vertical distribution of moisture in the plants, and its seasonal and sub-daily variation. Then, these measurements were used to define different sublayers in a multi-layer water cloud model (WCM). To calibrate and validate the WCM, we used hyper-temporal tower-based polarimetric L-band scatterometer data. WCM simulations showed a shift in dominant scattering from the lowest 50 cm to 50\u2013100 cm during the season in all polarizations, mainly due to leaf and ear growth and corresponding scattering and attenuation. Dew and rainfall interception raised sensitivity to upper parts of the canopy and lowered sensitivity to lower parts. The methodology and results presented in this study demonstrate the importance of the vertical moisture distribution on scattering from vegetation. These insights are essential to avoid misinterpretation and spurious artefacts during retrieval of soil moisture and vegetation parameters.<\/jats:p>","DOI":"10.3390\/rs14163867","type":"journal-article","created":{"date-parts":[[2022,8,10]],"date-time":"2022-08-10T04:20:32Z","timestamp":1660105232000},"page":"3867","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Towards Understanding the Influence of Vertical Water Distribution on Radar Backscatter from Vegetation Using a Multi-Layer Water Cloud Model"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7128-4256","authenticated-orcid":false,"given":"Paul C.","family":"Vermunt","sequence":"first","affiliation":[{"name":"Department of Water Management, Delft University of Technology, Stevinweg 1, 2628 CN Delft, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8644-3077","authenticated-orcid":false,"given":"Susan C.","family":"Steele-Dunne","sequence":"additional","affiliation":[{"name":"Department of Geoscience and Remote Sensing, Delft University of Technology, Stevinweg 1, 2628 CN Delft, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0236-1611","authenticated-orcid":false,"given":"Saeed","family":"Khabbazan","sequence":"additional","affiliation":[{"name":"Department of Water Management, Delft University of Technology, Stevinweg 1, 2628 CN Delft, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0469-3815","authenticated-orcid":false,"given":"Vineet","family":"Kumar","sequence":"additional","affiliation":[{"name":"Department of Geoscience and Remote Sensing, Delft University of Technology, Stevinweg 1, 2628 CN Delft, The Netherlands"}]},{"given":"Jasmeet","family":"Judge","sequence":"additional","affiliation":[{"name":"Center for Remote Sensing, Agricultural and Biological Engineering Department, University of Florida, Gainesville, FL 32611, USA"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"564","DOI":"10.1109\/LGRS.2011.2174772","article-title":"Radar Vegetation Index for Estimating the Vegetation Water Content of Rice and Soybean","volume":"9","author":"Kim","year":"2012","journal-title":"IEEE Geosci. 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